Hold down the Control and Shift keys, and right-click on a blank space in the Start menu.

Choose "Exit Explorer."

Open the Task Manager (Ctrl+Shift+Esc), navigate to File->Run, enter "explorer" and hit OK.

Why would you ever want to restart Explorer, you might ask? To try out new system modifications, for one, or try and rescue your desktop from crashing. In any case, the Geek's method gives Explorer a chance to properly close down and protect against any strange occurrences down the road. Hit the link for details on the "Classic" method of performing this trick.